Quality of life and psychological health indicators in the national social life, health, and aging project.

BACKGROUND The National Social Life, Health, and Aging Project (NSHAP) measures seven indicators of quality of life (QoL) and psychological health. The measures used for happiness, self-esteem, depression, and loneliness are well established in the literature. Conversely, measures of anxiety, stress, and self-reported emotional health were modified for their use in this unique project. The purpose of this paper is to provide (a) an overview of NSHAP's QoL assessment and (b) evidence for the adequacy of the modified measures. METHODS First, we examined the psychometric properties of the modified measures. Second, the established QoL measures were used to examine the concurrent validity of the modified measures. Finally, gender- and age-group differences were examined for each modified measure. RESULTS The anxiety index exhibited good internal reliability and concurrent validity. Consistent with the literature, a single-factor structure best fit the data. Stress was satisfactory in terms of concurrent validity but with only fair internal consistency. Self-reported emotional health exhibited good concurrent validity and moderate external validity. CONCLUSIONS The modified indices used in NSHAP tended to exhibit good internal reliability and concurrent validity. These measures can confidently be used in the exploration of QoL and psychological health in later life and its many correlates.